A taper roller bearing has a larger load capacity compared to another rolling bearing having the same size and has high rigidity.
FIG. 19 is a longitudinal sectional view illustrating a taper roller bearing 100 of the related art. The taper roller bearing 100 includes an inner ring 101, an outer ring 102, a plurality of taper rollers 103 which are provided between the inner ring 101 and the outer ring 102, and an annular cage 104 which holds the taper rollers 103 at an interval in the circumferential direction (for example, refer to Patent Document 1).
The cage 104 includes a small-diameter annular portion 105 on one axial side, a large-diameter annular portion 106 on the other axial side, and a plurality of column portions 107 which link the annular portions 105 and 106 to each other. In addition, a space formed between both of the annular portions 105 and 106 and between the column portions 107 and 107 adjacent to each other in the circumferential direction is a pocket 108 which accommodates the taper roller 103 therein.
In addition, in the taper roller bearing 100, a diameter of an inner circumferential surface of the outer ring 102 widens as approaching the other side from one axial side, and when the taper roller bearing 100 (for example, inner ring 101) rotates, an action (pump action) by which the lubricating oil flows from one axial side to the other side between the outer ring 102 and the inner ring 101 is generated. It is known that, by the pump action which follows the rotation of the taper roller bearing 100, the lubricating oil on the outside of the bearing flows to the inside of the bearing from one axial side, and flows out from the other axial side.